728867021 has 8 divisors (see below), whose sum is σ = 737003904. Its totient is φ = 720743040.

The previous prime is 728867011. The next prime is 728867059. The reversal of 728867021 is 120768827.

728867021 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-728867021 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 728867021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (728867011) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 149996 + ... + 154778.

It is an arithmetic number, because the mean of its divisors is an integer number (92125488).

Almost surely, 2^728867021 is an apocalyptic number.

It is an amenable number.

728867021 is a deficient number, since it is larger than the sum of its proper divisors (8136883).

728867021 is a wasteful number, since it uses less digits than its factorization.

728867021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6451.

The product of its (nonzero) digits is 75264, while the sum is 41.

The square root of 728867021 is about 26997.5373136144. The cubic root of 728867021 is about 899.9452728039.

The spelling of 728867021 in words is "seven hundred twenty-eight million, eight hundred sixty-seven thousand, twenty-one".